import React, {PureComponent} from 'react'

class About extends PureComponent {
  
  constructor(){
    console.log('dom挂载')
    super()
    this.state = {
      count: 1
    }
  }

  render () {
    console.log('render函数执行了')
    return (
      <div className="App">
       {this.state.count}
       <button onClick={()=>{this.setState({count: this.state.count + 5})}}>点击</button>
      </div>
    );
  }

  componentDidUpdate () {
    console.log('更新完成')
  }
}

export default About;
